There has been little examination of how criminological theory may help to inform library practice in correctional settings. This article takes steps to address this deficit by presenting a new and timely approach to prison library research. It suggests that situating prison library research within the disciplines of librarianship, education and criminology can lead to a deeper understanding of the contribution made by libraries to the lives of those in prison. The authors propose a theoretical model which draws on theories of desistance, informal learning theories and critical librarianship. This model can be used by both library and education researchers and practitioners to build a body of evidence on the value of the prison library, and may act as a roadmap to good practice. It is an initial framework, intended to be adapted and refined as more empirical evidence is collected in this area